Methyltransferases are a diverse group of enzymes that methylate proteins, DNA, and small molecule targets. Accordingly, methyl transferase activity plays a critical role in modulating gene transcription, protein interactions, and signaling networks. Anomalous DNA methylation patterns have been consistently detected during cancer development as well as in many genetic disorders such as Fragile X Syndrome, ICF, and Rett Syndrome. BioVision's Methyltransferase Activity Assay Kit (Colorimetric) allows for kinetic evaluation of methyltransferase activity of purified enzymes and their inhibitors. The transfer of a methyl group from S-Adenosyl Methionine (SAM) cofactor to a corresponding substrate generates S-Adenosyl Homocysteine (SAH) as a prod